Bad flowing of video sequence: Firewire or iMovie problem ?

[melodiastream]

Hello everybody. I'm new of this forum.
I have a DV Camera, and tried to live capture into iMovie 10.1.9 and Quicktime on my Early 2011 MacBook Pro, High Sierra OS, using the dv out of my camera (IEEE 1394, 400 Mb/s) into the Mac Firewire input (up to 800 Mb/s).

Both during the preview both when shooting a scene a strange phenomena happens. The video sequence is not flowing. It latches more than one time for few moments.
It seems that the mac is not able to correctly follow the camera's frame-rate and losses some frames.

Questions.
1 - Is maybe due to iMovie or Quicktime ?
2 - Is maybe due to the mac Firewire interface ? Is the Mac Firewire interface an IEEE 1394 ?
3 - What else ?

Solution's proposals are welcome.

Thanks very much in advance.

Melody.

 

[kohlson]

I suspect this is a symptom related to not able to process (capture/transmit/process/store) fast enough. That is, real time. It could be any of these. I would start with the disk. If it's original (5400 RPM and 9 years old, maybe full or fragmented) then that could be it. Could also be a shortage of memory (are all other apps closed?)

 

[melodiastream]

Kohlos,
thanks for your reply.
It really seems a real time process issue. However,

- The hard disk is a brand new Crucial MX500 250GB.
- The RAM is the 4GB original one.

Obviously, running iMovie I close all other apps.

What else could it be?

Could the problem depends on firewire interface ? Or maybe by not correct settings of the video capture drivers used by iMovie or Quicktime ?
How can I change the user settings of video capture drivers on a Mac book Pro ?

Thanks very much in advance.

Melody.

 

[kohlson]

Some suggestions:
- Can you add more RAM?
- Can you adjust the camera settings to lower resolution or bit rate, if only to try and get more information on the problem? I don't think you can adjust the capture settings on Quicktime. I don't think you can in iMovie, but you can make the Project Setting a lower resolution and see if the helps.
- Are there apps running that were started as part of the System Prefs - Users - Login Items?

Some thoughts:
- Capturing video requires a lot of computing resources. Playing video also requires resources. Doing both together requires lots of resources.
- Are you trying to run iMovie, and Quicktime at the same time? If so, this is very compute intensive.
- I am unaware of any way to adjust video capture drivers on a Mac.
- The Firewire interface is not the issue. It is very fast for this type workload.